I'm just gonna steal a comment from someone else: Hi and welcome to UX.se. As your question stands it's essentially asking for a review. However, reviews aren't part of the philosophy of this site as they have limited use to other users. You can still get useful feedback if you rephrase the question and focus on the specific UX problem.
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Koen LageveenMay 27 '13 at 18:35

Yep I figured out it was either a popup either increase the row height while in edit mode. Was hoping for some magical alternative ^^ Will probably go for the popup. Thanks
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ThunderDevJun 18 '13 at 20:02

=>The mock up is quite neat and self explanatory, it seems to be a generic solution though, as it does'nt specifically talk about the module being a part of Desktop or web app. Solutions can vary based on that knowledge.
=>Using Pop or an extended side panel is not a bad solution but in this particular scenario since you have only 3 items to be entered/selected by user, you can very well use the original space in the column 4 (Roles) of the data grid. Once a user clicks edit, that particular cell should expand so that the user can select the role, date and level somewhat like this -

Just realized that you have mentioned about building a site, in that case, pop ups should not be there unless absolutely necessary as it is cumbersome for users to interact with something popping up every time he needs to enter/edit a record.
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PhoenixMay 27 '13 at 16:57

I just updated the mock up, as you can see I don't have quite enough space for extending the grid. Thanks for the input
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ThunderDevMay 27 '13 at 17:20

Your design quite reasonable. I just want to point a little detail.
As level has discrete values it is better to display fixed values. Also it is important that all the values are visible for user. And too many choises are complicated for users!